Musculoskeletal and Connective Tissue Flashcards Preview

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Flashcards in Musculoskeletal and Connective Tissue Deck (168):
1

Unhappy Triad
Context of injury?
What happens?
Tears?
Treatment

Common injury in contact sports
Lateral force applied to planted leg
Tear of ACL, MCL (medial or tibial collateral ligament) and Meniscus (classically medial but lateral more common)
Surgical ACL reconstruction

2

Positive anterior drawer sign

ACL tear

3

Abnormal passive abduction of the leg

MCL tear

4

ACL attachments and function

Lateral condyle of the femur to the anterior intercondylar area of the tibia
Prevents femur from shifting backwards

5

PCL attachments and function

Medial condyle of the femur to the posterior intercondylar area of the tibia
Prevents femur from shifting forward

6

Pudendal nerve block
Function
Location

Relieve pain of delivery
Ischial Spine

7

Location of lumbar puncture in adults

Iliac Crest (L3-4 or L4-5)

8

Rotator Cuff Muscles
Function
Attachement
Innervation

"Superman Subsumes his Inferior Minors"
Supraspinatus - Abducts before deltoid. Most common injury. Attaches superiorly
Infraspinatus - Lateral rotation. Pinching injury. Attaches posteriorly
Teres Minor - Adducts and lateral rotation. Attaches posteriorly
Subscapularis - medial rotates and adducts. Attaches anteriorly
C5-C6

9

Writs Bones (Carpals)

"So Long To Pinky, Here Comes The Thumb"
Closest to arm, Thumb to Pinky
Scaphoid, Lunate, Triquetrum
Closest to fingers, Pinky to Thumb
Pisiform, Hamate, Capitate, Trapezoid

10

Most commonly fractured carpal? Other risks to this bone?

Scaphoid. Prone to avascular necrosis owing to retrograde blood supply

11

Cause of acute carpal tunnel syndrome

Dislocation of the lunate

12

Carpal Tunnel Syndrome
PathoPhys
Presentation

Entrapment of median nerve in carpal tunnel
Paresthesia, pain and numbness in median nerve area.

13

Median Nerve Sensation

Anterior: thumb side of hand, 1st, 2nd, and half of 3rd fingers
Posterior: 1st, 2nd, and half of 3rd fingers

14

Innervation of Palm of Hand

Thumb side - median nerve
Pinky side - Ulnar nerve

15

Innervation of Back of Hand

Thumb side - Radial nerve (superficial branch)
Pinky side - Ulnar nerve
1st, 2nd, and 3rd fingers - Median nerve

16

Innervation of top of shoulder?

C4

17

Innervation of lateral side of upper arm?

C5

18

Innervation of lateral side of lower arm?

C6

19

Innervation of medial side of lower and most of upper arm?

T1

20

Innervation of Axilla

T2

21

Injury to lower trunk of brachial plexus
What can cause it?
What does it produce?

Compressed by cervical rib or Pancoast tumor of lung
Produces Klumpke's Palsy

22

How and where is Radial nerve injured
Roots of radial nerve?
Motor manifestation of injury?
Sensory manifestation of injury?
Manifestation of injury?

Compressed in axilla by incorrect use of a crutch
Lesioned by midshaft fracture of humerus in spiral groove
Deep branch stretched by subluxation of radius
Posterior cord (C5-T1)
"BEST extensors"
Brachioradialis, Extensor of wrist and fingers, Supinator, Triceps
Posterior arm and dorsal hand and thumb
Saturday night palsy (wrist drop)

23

How is upper trunk of brachial plexus injured?

Trauma

24

Axillary nerve?
How is it injured?
Roots?
Motor manifestation of injury?
Sensory manifestation of injury?
Sign of injury?

Lesioned by fracture of surgical neck of humerus, dislocation of humeral head, or intramuscular injections
Posterior cord (C5, C6)
Deltoid paralysis (problem with abduction at shoulder).
Sensory loss of deltoid muscle.
Deltoid atrophy

25

Where is the anterior interosseous nerve injured?

Compressed in deep forearm

26

What is the cause of injury to recurrent branch of the median nerve?

Lesioned by superficial laceration

27

Bones of arm

Humerus
Ulna (pinky side)
Radius (thumb side)

28

Attachments of Flexor Retinaculum

Scaphoid and Trapezium to Pisiform and Hook of hamate

29

Abductor Pollicis Brevis
Origin
Insertion
Innervation
Action

Flexor Retinaculum, Scaphoid, Trapezius
Lateral side of proximal phalanx of the thumb
Recurrent branch of median nerve
Abducts the thumb

30

How does the ulnar nerve enter the hand? Possible pathology?

Through Guyon's Canal
Guyon's Canal Syndrome

31

Abductor digiti minimi
Origin
Insertion
Innervation
Action

Pisiform and tendon of flexor carpi ulnaris
Medial side of base of proximal phalanx of little finger
Ulnar nerve
Abducts little finger

32

hypothenar

Pinky side

33

Thenar

Thumb side

34

Flexor Pollicis Brevis
Origin
Insertion
Innervation
Action

FR and Trapezius
Base of proximal phalanx of thumb
Median nerve
Flexes thumb

35

Opponens Pollicis
Origin
Insertion
Innervation
Action

FR and Trapezius
1st metacarpal
Median
Opposes thumb to other digits

36

Adductor Pollicis
Origin
Insertion
Innervation
Action

Oblique head: Capitate and base of 2nd and 3rd metacarpals
Transverse head: 3rd metacarpal
Proximal phalanx of thumb
Ulnar nerve
Adducts thumb

37

Palmaris Brevis
Origin
Insertion
Innervation
Action

FR, Palmar aponeurosis
Skin of medial palm
Ulnar
Wrinkles skin

38

Flexor Digiti Minimi Brevis
Origin
Insertion
Innervation
Action

FR and hook of hamate
Proximal Phalanx of pinky
Ulnar
Flexes

39

Opponens Digiti Minimi
Origin
Insertion
Innervation
Action

FR and hook of hamate
5th metacarpal
Ulnar
Opposes pinky

40

Lumbriclas
#
Origin
Insertion
Innervation
Action

4
Tendons of Flexor Digitorum Profundus
Lateral sides of extensor expansions
Lateral 2: Median
Medial 2: Unlar
Flexes metacarpophalangeal joints and extends interphalangeal joints

41

Dorsal interossei
#
Description
Origin
Insertion
Innervation
Action

"DAB"
4
Bipennate
Adjacent sides of metacarpal bones
Lateral sides of proximal phalanges
Ulnar
Abducts fingers, flexes metacarpophalangeal joints and extends interphalangeal joints

42

Palmar Interossei
#
Description
Origin
Insertion
Innervation
Action

"PAD"
3
Unipennate
Medial side of 2nd metacarpal
Lateral sides of 4th and 5th metacarpals
Proximal phalanges
Ulnar
Adducts fingers, flexes metacarpophalangeal joints and extends interphalangeal joints

43

Divisions of the Brachial Plexus

"Real Texans Drink Cold Bear"
Roots
Trunks
Divisions
Cords
Branches

44

Upper trunk of the Brachial Plexus
Roots?
Injury?

C5-C6
"Waiter's Tip" - Erb's Palsy

45

Lower Trunk of Brachial Plexus
Roots?
Injury?

C8, T1
Claw hand - Klumpke's Palsy

46

Posterior Cord of Brachial Plexus
Roots?
Injury?

C5-T1
Wrist Drop

47

Long Thoracic Nerve
Roots?
Muscles innervated w/ function?
Context and consequences of Injury?

C5-C7
Serratus Anterior anchors scapula to thoracic cage. Used for abduction above horizontal position
Injured in mastectomy --> Winged Scapula and ipsilateral lymphedema

48

Musculocutaneous nerve
Roots?
Cause of injury?
Motor deficit?
Sensor deficit?
Manifestation of injury?

C5-C7
Upper Trunk Compression
Biceps, Brachialis, Coracobrachialis, Flexion of arm at elbow
Lateral forearm
Difficulty flexing the elbow. Variable sensory loss

49

Median nerve
Causes of injury?
Roots
Motor deficit
Sensory deficit
Manifestation of injury?

Compressed in supracondylar fracture of humerus producing pronator teres syndrome
Compressed in carpal tunnel syndrome and by dislocation of lunate
C5-T1
Opposition of thumb, Lateral finger flexion, Wrist flexion
Lateral hand
Decreased Thumb Function (pope's blessing)

50

Ulnar Nerve
Causes of injury?
Roots?
Motor deficit
Sensory deficit?
Sign

Lesioned by repeat minor traumas, Fracture of medial epicondyle of humerus, Trauma to heel of the hand, Fracture to hook of hamate
C8, T1
Medial finger flexion, Wrist flexion
Pinky side of hand
Radial deviation of wrist upon wrist flexion, Ulnar Claw

51

What protects the brachial plexus when the clavicle is fractured?

Subclavius muscle

52

Muscles innervated by Dorsal Scapular Nerve

Rhomboids and Levator Scapulae

53

Suprascapular nerve
What muscles does it innervate?
Roots

Supra and Infra spinatus
C5, C6

54

Lateral Pectoral Nerve
Roots?
Muscles innervated?

C5-C7
Pectoralis Major

55

Thoracodorsal Nerve
Roots
Muscles innervated

C7, C8
Latissimus Dorsi

56

Erb-Duchenne Palsy
Nickname
Site of lesion
Context of injury
Findings

Waiters Tip
Upper Trunk of Brachial Plexus (C5, C6)
Seen in infants following trauma during delivery
Limb hangs by side (paralysis of abductors - suprascapular and deltoid), Medially rotated (paralysis of lateral rotators), Forearm pronated (loss of biceps)

57

Klumpke's Palsy
Site of lesion
Context of injury
Complication
Findings

Lower trunk of brachial plexus (C8, T1)
Embryological or childbirth defect
Cervical rib can compress subclavian artery and Lower Trunk resulting in Thoracic Outlet Syndrome
Atrophy of thenar and hypothenar eminences, Atrophy of interosseous muscles, Sensory deficits on medial side of forearm and hand, Loss of radial pulse when head moved to ipsilateral side

58

Clawing

Loss of lumbricals which flexes the MCP joints and extends the DIP and PIP joints

59

Ulnar Claw
Cause of lesion
PathoPhys

Long standing injury to ulnar nerve at hook of hamate (falling)
Distal Ulnar lesion --> Loss of medial lumbricals --> inability to extend 4th and 5th digits

60

Medial Claw
Caused by
PathoPhys

Carpal Tunnel Syndrome or Dislocated Lunate
Distal median nerve injury (after branch containing C5-C7 branches off to feed forearm flexors) --> Loss of lateral lumbricals --> Clawing of 2nd and 3rd fingers

61

Pope's Blessing
PathoPhys
Findings

Proximal median nerve lesion causes loss of lateral finger flexion and thumb opposition.
When asked to make a fist, 2nd and 3rd fingers remain extended and thumb remains unopposed

62

Ape Hand

Proximal median nerve lesion --> loss of opponens pollicis muscle function --> unopposable thumb (cannot abduct the thumb)

63

Klumpke's Total Claw
Site of lesion
PathoPhys

Lesion to lower trunk (C8, T1) of Brachial plexus
Loss of function of all lumbricals --> Forearm finger flexors (fed by median nerve with C5-C7) and finger extensors (fed by Radial nerve) are unopposed --> clawing of all digits

64

Thenar eminence muscles

Opponens pollicis, Abductor pollicis brevis, Flexor pollicis brevis

65

Hypothenar eminence mucles

Opponens digiti minimi, Abductor digiti minimi, Flexor digiti minimi

66

Obturator Nerve
Roots
Cause of injury
Motor deficit
Sensory deficit

L2-L4
Anterior hip dislocation
Thigh Adduction
Medial Thigh

67

Femoral Nerve
Roots
Cause of injury
Motor deficit
Sensory deficit

L2-L4
Pelvic fracture
Thigh flexion and leg extension
Anterior thigh and medial leg

68

Common Peroneal nerve
Roots
Cause of injury
Motor deficit
Sensory deficit

L4-S2
Trauma or compression of lateral aspect of leg or fibula neck fracture
"PED"
Foot eversion and dorsiflexion, toe extension, foot dropPED, foot slap, steppage gait (Peroneus longus and brevis)
Anterolateral leg and dorsal aspect of food

69

Tibial Nerve
Roots
Cause of injury
Motor deficit
Sensory deficit

L4-S3
Knee trauma
"TIP"
Foot inversion and plantarflexion (cannot stand on TIPtoes), toe flexion
Sole of foot

70

Superior Gluteal Nerve
Roots
Cause of injury
Motor deficit

L4-S1
Posterior hip dislocation or polio
Thigh abduction (positive trendelenburg sign)

71

Trendelenberg Sign
What is it?
What does it mean?

Contralateral hip drop when standing on leg ipsilateral to site of lesion
Sign of injury to Gluteus minimus or medius (abductors of the hip)

72

Inferior Gluteal Nerve
Roots
Cause of injury
Motor deficit

L5-S2
Posterior hip dislocation
Cant jump, climb stairs, rise from seated position, push inferiorly

73

Sciatic nerve
Roots
Sensory area
Branches

L4-S3
Posterior thigh
Splits into common peroneal and tibial nerve

74

Steps of Ca entrance into skeletal muscles

1. ACh binding --> muscle depolarization at motor end plate
2. Depolarization travels along T tubule
3. V gated Dihydrophyridine receptors mechanically coupled to Ryanodine receptors in SR
4. Ca from SR enters cell

75

How does Ca activate muscles

1. Ca --> troponin C
2. Troponin C moves tropomyosin out of myosin binding groove on actin filaments

76

Steps of skeletal and cardiac muscle contraction

1. ATP hydrolysis cocks myosin head
2. Tropomyosin displaced and myosin binds actin
3. P released --> power stroke
4. ADP released and ATP binds allowing separation of myosin and actin

77

During contraction, what happens to the bands in the skeletal muscle

Shortening H and I bands and between Z line (HIZ shrinkage)
A band remains the same length (A always the same)

78

Type 1 Muscle
Speed
Length of contraction
Color
Primary Reaction

"1 Slow Red Ox"
Slow twitch, Sustained contraction
Red fibers (from ↑ mito and myoglobin)
Oxidative phosphorylation

79

Type 2 Muscle
Speed
Color
Primary Reaction
What kind of training affects them?

Fast twitch
White fibers (↓ mito and myoglobin)
Anaerobic glycolysis
Weight training --> hypertrophy

80

Z line

Where actin attaches to backbone

81

I band

Just Actin

82

H band

Just Myosin

83

A band

Myosin + Where Myosin overlaps with Actin

84

M line

Center of myosin

85

Endochondral Ossification
Which bones form this way?
Process

Axial and appendicular skeleton and base of skull
Cartilaginous model of bone is made by chondrocytes. Osteoclasts and Osteoblasts later replace with woven bone and then remodel to lamellar bone

86

In adults, when does woven bone occur?

After fractures or in Paget's disease

87

Membranous ossification
Which bones form this way?
Process

Calavarium and facial bones
Woven bone forms directly w/o cartilage. Later remodeled to lamellar bone

88

Osteoblasts
Function
Derived from?

Build Bone by secreting collagen and catalyzing mineralization
Differentiate from mesenchymal stem cells in periosteum

89

Osteoclasts
Histo
Function
Derived from?

Multinucleated cells
Dissolve bone by secreting acid and collagenases
Differentiate from monocytes/macrophages

90

Affects of PTH on Bone

At low, intermittent levels, exert anabolic affects (building bone) on osteoblasts and (indirectly) osteoclasts.
Primary hyperparathyroidism --> catabolic affects (osteitis fibrosa cystica)

91

Affects of Estrogen on Bone

Estrogen --/ apoptosis in bone forming osteoblasts and induces apoptosis in bone-resorbing osteoclasts

92

Achondroplasia
What is it?
PathoPhys
Genetics
Presentation

Failure of longitudinal bone growth (endochondral ossification) --> short limbs. Membranous ossification not affected --> Large head relative to limbs.
Constitutive activation of Fibroblast Growth Factor Receptor 3 (FGFR3) inhibits chondrocyte proliferation
More than 85% of mutations are sporadic and associated with advanced paternal age. Condition also shows Autosomal Dominant inheritance
Dwarfism. Normal lifespan and fertility

93

Osteoporosis
What is it?
Lab Values
What can in lead to?

Trabecular (spongy) bone loses mass and interconnections despite normal bone mineralization
Normal lab values (serum Ca and PO4)
Vertebral Crush Fractures (Acute back pain, Loss of height, Kyphosis)

94

Osteoporosis Type 1
Context
PathoPhys
Areas affected

Postmenopausal
↑ bone resorption due to ↓ estrogen
Femoral neck fracture, distal radius (Colles' fracture)

95

Osteoporosis Type 2
Context
Prophylaxis
Treatment
Contraindications

Men and Women > 70 years old
Regular weight bearing exercise, Ca and Vit D intake
SERMs (estrogen) +/or Calcitonin, Bisphosphonates or pulsatile PTH for severe cases
Glucocorticoids are contraindicated

96

Osteopetrosis
AKA
PathoPhys
Description of bones
Consequences of bone pathology?

Marble Bone Disease
Failure of normal bone resorption due to defective osteoclasts. Mutations (Carbonic Anhydrase II) impairs ability of osteoclasts to generate acidic environment necessary for bone resorption
Thickened, dense bones that are prone to fracture.
Bone fills marrow space causing pancytopenia, extramedullary hematopoiesis

97

Osteopetrosis
XR
Complications
Treatment

Bone-in-bone appearance
Cranial nerve impingement and palsies b/c of narrow foramina
Bone marrow transplant because osteoclasts derived from monocytes

98

Osteomalacia/Rickets
Population affected
PathoPhys
Findings

Adults: Osteomalacia, Children: Rickets
Defective mineralization/calcification of osteoid. ↓ VitD --> ↓ serum Ca --> ↑ PTH --> ↓ serum Phosphate
Hyperactive osteoblasts --> ↑ AlkPhos (osteoblasts require alkaline environment)

99

Paget's Disease of Bone
AKA
Frequency
PathoPhys
Findings
Description of bone
Fractures?
Complications
Presentation

Osteitis Deformans
Common
Localized bone remodeling disorder causes by ↑ in osteoblasts and osteoclasts
Serum Ca, PO4, and PTH normal. ↑ ALP
Mosaic (woven) bone pattern
Long bone chalk-stick fractures
↑ blood flow from ↑ arteriovenous shunts --> high output heart failure
↑ risk of osteogenic sarcoma
Hat size ↑, hearing loss (auditory foramen narrowing)

100

Osteoporosis
Serum Ca
Serum PO4
ALP
PTH
Bone description

-
-
-
-
↓ Bone Mass

101

Osteopetrosis
Serum Ca
Serum PO4
ALP
PTH
Bone description

↓Ca
No change in PO4
↑ ALP
No change in PTH
Thickened, dense bones

102

Osteomalacia/Rickets
Serum Ca
Serum PO4
ALP
PTH
Bone description

↓ Ca
↓ PO4
↑ ALP
↑ PTH
Soft Bones

103

Osteitis Fibrosa Cystica
Serum Ca
Serum PO4
ALP
PTH
Bone description

↑ Ca
↓ PO4
↑ ALP
↑ PTH
"Bone tumors" of hyperparathyroidism

104

Paget's Disease
Serum Ca
Serum PO4
ALP
PTH
Bone description

No change in Ca
No change in PO4
↑ ALP
No change in PTH
Abnormal bone architecture

105

Polyostotic Fibrous Dysplasia
PathoPhys
Name of a form of it?

Bone replaced by fibroblasts, collagen, and irregular bony trabeculae
McCune-Albright Syndrome characterized by multiple unilateral bone lesions associated with endocrine abnormalities (precocious puberty) and cafe-au-lait spots

106

Giant Cell Tumor of Bone
Name
Epidemiology
Location
Malignant?
XR
Histo

Osteoclastoma
20-40 year olds
Epiphyseal end of long bones: distal femur, proximal tibial region (knee)
Locally aggressive benign tumor
Double bubble or soap bubble appearance
Spindle-shaped cells with multinucleated giant cells

107

Osteochondroma
Name
Frequency
Epidemiology
Location
Description
Malignant?

Exostosis
Most common benign tumor
Males

108

Osteosarcoma
Name
Frequency
Epidemiology
Prognosis
Treatment

Osteogenic sarcoma
2nd most common primary malignant bone tumor (after multiple myeloma)
Male > female, 10-20 years old
Aggressive
Surgical en bloc resection (with limb salvage) and chemotherapy

109

Metaphysis

Wider portin of long bone adjacent to epiphyseal plate

110

Osteosarcoma
Predisposing factors
Location
XR

Paget's disease of bone, Bone infarcts, Radiation, Familial Retinoblastoma
Metaphysis of long bone often around distal femur and proximal tibial region (knee)
Codman's Triangle (from elevation of periosteum) or sunburnt pattern

111

Ewing's Sarcoma
Epidemiology
Location
Histo
Malignant?

Boys

112

Ewing's Sarcoma
XR
Genetics
Prognosis
Treatment

Onion skin appearance in bone
t(11;22) translocation
Extremely aggressive with early mets
Responsive to chemotherapy

113

Chondrosarcoma
Epidemiology
Location
Malignant
Type of tissue?
Origin?
Gross

Men 30 - 60
Diaphysis. Pelvis, Spine, Scapula, Humerus, Tibia, Femur
Malignant
Cartilaginous
Primary or from osteochondroma
Expansive glistening mass within medullary cavity

114

Osteoarthritis
Etiology
Predisposing factors
Treatment

Mechanical (wear and tear) destruction of articular cartilage
Age, Obesity, Joint deformity
NSAIDs, Intra-articular glucocorticoids

115

Osteoarthritis
Presentation
XR
Gross

Pain in weight-bearing joints after use (at end of day), Improves with rest, Knee cartilage loss begins medially (bowlegged), No systemic symptoms, Not inflammatory
Subchondral cysts, Sclerosis, Joint narrowing, Osteophytes (bone spurs)
Eburnation (polished, ivory like appearance of bone), Ulcerated cartilage, Thickened capsule, Synovial hypertrophy, Bouchard's nodes (PIP), No MCP involvement

116

Rheumatoid Arthritis
Etiology
Histo
Gross
Regions involved

Autoimmune - inflammatory destruction of synovial joints. Type III hypersensitivity reaction
Pannus formation in joints (MCP and PIP), Increased synovial fluid, Bone and Cartilage erosion
Subcutaneous rheumatoid nodules (fibrinoid necrosis), Ulnar deviation in fingers, Subluxation, Baker's Cyst (in popliteal fossa)
MCP and PIP, No DIP

117

Rheumatoid Arthritis
Epidemiology
Labs
HLA
Presentation
Treatment

Females > Males
80% have RF+ (anti IgG Ab), Anti-cyclic citrullinated peptide Ab (specific)
HLA-DR4
Morning stiffness lasting >30 minutes and improving with use. Systemic joint involvement and systemic symptoms (fever, fatigue, pleuritis, pericarditis)
NSAIDs, Glucocorticoids, Disease modifying agents (Methotrexate, Sulfasalazine, TNFα inhibitors)

118

Sjogren's Syndrome
PathoPhys
Locations
Classic Presentation
Risks
Labs
Epidemiology
Associated with what other disease?

Lymphocytic infiltration of exocrine glands
Especially lacrimal and salivary glands
Xerophthalmia (dry eyes, conjunctivitis, "sand in my eyes"), Xerostomia (dry mouth, dysphagia), Arthritis, Parotid enlargement
Risk of B cell lymphoma, dental caries
Auto Abs to ribonucleoprotein antigens: SS-A (Ro), SS-B (La)
Females between 40 and 60
Rheumatoid Arthritis

119

Gout
PathoPhys
Causes
Epidemiology
Crystals

Precipitation of monosodium Urate Crystals into joints due to hyperuricemia
Lesch-Nyhan syndrome, PRPP excess, ↓ excretion of uric acid (thiazide diuretics), ↑ cell turnover, von Gierke's disease. 90% due to underexcretion, 10% due to overproduction.
More common in men
Crystals are needle shaped and negatively birefringent (yellow crystals under parallel light)

120

Gout
Distribution
Description of joints
Classic manifestation
Gross signs
When does it present?

Asymmetric joint distribution
Joints are swollen, red, and painful
Painful MTP (metatarsophalangeal) joint of the big toe (podagra)
Tophus formation (external ear, olecranon bursa, achilles tendon)
Acute attacks tend to occur after a large meal or EtOH consumption

121

Why does EtOH aggravate Gout

EtOH metabolites compete for same excretion sites in kidney as uric acid causing ↓ uric acid secretion

122

Pseudogout
What causes it?
Histo
Which joints affected?
Epidemiology
Treatment

Deposition of Ca pyrophosphate crystals w/in joint space
Basophilic rhomboid crystals that are weakly positively birefringent
Large joints (knee)
Older than 50, male and female equal
NSAIDs (sudden severe attacks), Steroids, Colchicine

123

Crystals in Gout vs Pseudogout

Gout: yellow when parallel to light
Pseudogout: blue when parallel to light

124

Infectious Arthritis
Causative agents
Presentation

S. aureus, Streptococcus, Neisseria gonorrhoeae
Joints are swollen, painful, and red
"STD"
Synovitis (knee), Tenosynovitis (hand), Dermatitis (pustules)

125

Gonoccal Arthritis

STD that presents as a migratory arthritis with an asymmetric pattern

126

Osteonecrosis
Name
What happens?
Presentation
What causes it?
Most common site?

Avascular necrosis
Infarction of bone and marrow
Pain associated with activity
Trauma, high-dose corticosteroids, alcoholism, sickle cell
Femoral head

127

Seronegative Spondyloarthropathies
What are they?
HLA
Epidemiology
Names

Arthritis w/o RF
HLAB27
Males
"PAIR"
Psoriatic arthritis, Ankylosing spondylitis, IBD, Reactive arthritis

128

Psoriatic Arthritis
What is it?
Distribution
Gross
XR
% of pts with psoriasis that get it?

Joint pain and stiffness associated with psoriasis
Asymmetric and patchy involvement
Dactylitis (sausage fingers)
Pencil in cup deformity on XR
1/3 of pts with psoriasis get it

129

Ankylosing Spondylitis
What is it? Where is it?
Presentation
XR

Chronic inflammatory disease of spine and sacroiliac joints
Ankylosis (stiff spine due to fusion of joints), Uveitis, Aortic Regurgitation
Bamboo spine (vertebral fusion)

130

Reactive Arthritis
Name
Presentation
Causes

Reiter's Syndrome
"Can't see, Can't Pee, Can't Climb a Tree"
Conjunctivitis and anterior uveitis, Urethritis, Arthritis, Palm and Sole Rash
Post GI or Chlamydia infection

131

Polymyalgia Rheumatica
Symptoms
Epidemiology
Associated with what other diseases?
Labs
Treatment

Pain and stiffness in shoulders and hips often with fever, malaise, and wt loss. Does not cause muscular weakness
More common in women > 50
Associated with Temporal Giant Cell Arteritis
↑ ESR. Normal CK
Rapid response to low-dose corticosteroids

132

Fibromyalgia
Epidemiology
Presentation
Secondary symptoms

Women 20-50
Chronic, widespread musculoskeletal pain
Associated with stiffness, paresthesia, poor sleep, and fatigue

133

Polymyositis
Presentation
Histo
Common location
Findings
Treatment

Progressive symmetric proximal muscle weakness
Endomysial inflammation with CD8+ T cells
Shoulders
↑ CK, ANA+, +anti Jo1 Abs
Steroids

134

Dermatomyositis
Presentation
Histo
Risks
Findings
Treatment

Progressive symmetric proximal muscle weakness with malar rash, Gottron's papules, Heliotrope rash, Shawl and Face rash, Mechanic hands
Perimysial inflammation and atrophy with CD4+ T cells
↑ risk of occult malignancy
↑ CK, ANA+, +anti Jo1 Abs
Steroids

135

Names of Neuromuscular Junction Diseases

Myasthenia gravis
Lambert-Eaton Myasthenic Syndrome

136

Myasthenia gravis
Frequency
Pathophysiology
Presentation
Associated w/
Treatment

Most common NMJ disorder
AutoAbs to postsynaptic ACh receptors
Ptosis, Diplopia, Weakness, Worsens with muscle use
Thymoma, Thymic hyperplasia
AChE inhibitors

137

Lambert-Eaton Myasthenic Syndrome
Frequency
Pathophysiology
Presentation
Associated w/
Treatment

Uncommon
AutoAbs to presynaptic Ca channels --> ACh release
Proximal muscle weakness that improves with muscle use
Small cell lung cancer
No effect with AChE inhibitors

138

Myositis Ossificans
What is it?
Location
Presentation

Metaplasia of skeletal muscle to bone following muscular trauma
Most often seen in upper and lower extremity
May present as suspicious mass at site of known trauma or as incidental finding on radiography

139

Lipoxygenase pathway yields...

Leukotrienes

140

LTB4

"Neutrophils Arrive Before Others"
Neutrophil chemotactic

141

LTC4, D4, and E4

Bronchoconstriction, Vasoconstriction, Contraction of Smooth Muscle, ↑ Vascular permeability

142

PGI2
Name
Function
Synthesis

Prostacyclin
"Platelet Gathering Inhibitor"
Inhibits platelet aggregation and promotes vasodilation. ↓ Bronchial tone, ↓ Uterine tone
Membrane lipids (eg phosphatidylinositol) --> [PLA2] --> Arachidonic Acid --> [COX] --> Endoperoxides (PGG2, PGH2) --> Prostacyclin (PGI2)

143

Leukotriene Synthesis

Membrane lipids (eg phosphatidylinositol) --> [PLA2] --> Arachidonic Acid --> [Lipoxygenase] --> Hydroperoxides (HPETEs) --> Leukotrienes

144

Prostaglandins
Names
Function
Synthesis

PGE2, PGF2α
↑ Uterine tone, ↓ Vascular tone, ↓ Bronchial tone
Membrane lipids (eg phosphatidylinositol) --> [PLA2] --> Arachidonic Acid --> [COX] --> Endoperoxides (PGG2, PGH2) --> Prostaglandins

145

Thromboxane
Names
Function
Synthesis

TXA2
↑ Platelet aggregation, ↑ Vascular tone, ↑ Bronchial tone
Membrane lipids (eg phosphatidylinositol) --> [PLA2] --> Arachidonic Acid --> [COX] --> Endoperoxides (PGG2, PGH2) --> Thromboxane

146

Aspirin
Mechanism
Net result
Class

Irreversibly inhibits COX1 and COX2 by acetylation
↓ synthesis of both TXA2 and Prostaglandins, ↑ bleeding time, No effect on PT of PTT
NSAID

147

Aspirin
Uses
Tox

Low dose (less than 300mg): ↓ platelet aggregation.
Intermediate dose (300-2400): antipyretic and analgesic.
High dose (2400-4000): anti-inflammatory
Gastric ulcers, Tinnitus (CNVIII), Chronci use can lead to acute renal failure, interstitial nephritis, upper GI bleed. Reyes syndrome in children. Stimulates respiratory centers leading to hyperventilation and respiratory alkalosis

148

NSAIDs
Names
Mechanism
Use
Tox

Ibuprofen, Naproxen, Indomethacin, Ketorolac, Diclofenac
Reversibly inhibits COX1 and COX2. Blocks Prostaglandin synthesis
Antipyretic, analgesic, anti-inflammatory. Indomethacin used to close PDA
Interstitial nephritis, Gastric ulcer, Renal ischemia

149

COX2 Inhibitors
Name
MoA
What does it Spare?

Celecoxib
Reversibly inhibits COX2 which is found in inflammatory cells and vascular endothelium and mediates inflammation and pain.
Spares COX1 and thus doesn't affect gastric mucosa. Also spares TXA2 and spares platelet function

150

COX2 Inhibitors
Use
Tox

RA and Osteoarthritis in pts with gastritis or ulcers
↑ risk of thrombosis. Sulfa allergy

151

Acetaminophen
MoA
Use
Tox

Reversibly inhibits COX, mostly in CNS. Inactivated peripherally
Antipyretic, analgesic, not anti-inflammatory. Used instead of aspirin to avoid Reyes Syndrome in children w/ viral infection
OD produces hepatic necrosis. Metabolite depletes glutathione and forms toxic tissue adducts in liver

152

Cure for Acetaminophen OD

N-acetylcysteine regenerates Glutathione

153

Bisphosphonates
Names
Kind of drug
MoA
Use
Tox

Alendronate, other -dronates
Pyrophosphate analog
Bind hydroxyapatite in bone and inhibits osteoclast activity
Osteoporosis, hyperCa, Paget's disease of bone
Corrosive esophagitis, Osteonecrosis of the jaw

154

Names of Gout Drugs

Allopurinol, Febuxostat, Probenecid, Colchicine

155

Allopurinol
MoA
Use
Findings w/ use
What drugs cannot go with it?
Affect on uric acid clearance?

Inhibits xanthine oxidase thus ↓ conversion of xanthine to uric acid
Gout, Lymphoma and Leukemia (to prevent tumor lysis and associated urate nephropathy).
↑ concentrations of azathioprine and 6MP (both normally metabolized by xanthine oxidase)
Do not give salicylates
All but highest doses depress uric acid clearance. Even high doses have only minor uricosuric activity

156

Febuxostat
MoA
Use

Inhibits xanthine oxidase
Gout

157

Probenecid
MoA
Use
Tox

Inhibits reabsorption of uric acid in PCT
Gout
inhibits secretion of penicillin

158

Colchicine
MoA
Use
Tox

Binds and stabilizes tubulin to inhibit polymerization thus impairing leukocyte chemotaxis and degranulation (decreases LTB4)
Gout
GI side effects, especially if given orally: diarrhea, abdominal pain, nausea
Myelosuppression

159

Acute drugs for gout

NSAIDs (Naproxen and Indomethacin)
Oral or Intramuscular Glucocorticoids

160

Risks of TNFα inhibitors

Predispose to infection including TB since TNF blockade prevents activation of macrophages and destruction of phagocytosed microbes

161

Etanercept
Class of drug
Description of drug
MoA
Use

"etanerCEPT is a TNF decoy reCEPTor"
TNFα inhibitors
Fusion protein: receptor for TNFα and IgG1 Fc produced by recombinant DNA
RA, Psoriasis, Ankylosing Spondylitis

162

Infliximab, Adalimumab
Class of drug
MoA
Use

TNFα inhibitors
Anti TNFα monoclonal Ab
RA, Psoriasis, Ankylosing Spondylitis, Crohn's Disease

163

Periosteum

A membrane that lines the outer surface of all bones, except at the joints of long bones.

164

Osteoid

Unmineralized bone

165

Bones of lateral foot

Posterior to anterior: Calcaneus and Cuboid

166

Bones of medial foot

Posterior to anterior: Talus and Navicular bones
Medial, Intermediate, and Lateral Cuneiforms

167

Sensory innervation of anterior leg

Deep Peroneal nerve: In between big toe and 2nd toe
Superficial Peroneal nerve: Top of foot and Lateral Leg
Sural Nerve: Lateral foot
Saphenous nerve (L3-L4): Medial leg and medial knee
Femoral nerve: Anterior and lateral thigh
Obturator nerve: Medial thigh


168

Sensory innervation of posterior leg

Tibial nerve: plantar surface of foot
Sural nerve: lateral leg
Saphenous nerve: Medial leg
Femoral nerve: Lateral thigh
Sciatic nerve: Posterior thigh